<template>
  <div class="about">
    <button @click="add">This is an about page</button>
    a->{{ a }}
  </div>
</template>
<script>
export default {
  data() {
    return {
      a: '1',
    };
  },
  methods:{
    add(){
      this.a++
    }
  },
  beforeCreate() {},
  created() {},
  beforeMount() {},
  mounted() {},
  beforeUpdate() {
    console.log(2);
  },
  updated() {
    console.log(3);
  },
  beforeDestroy() {},
  destroyed() {},
};
</script>
